A012752 - OEIS

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A012752

exp(arctanh(x)*arcsinh(x)) = 1+2/2!*x^2+16/4!*x^4+398/6!*x^6+18072/8!*x^8...

1, 2, 16, 398, 18072, 1465962, 169054092, 28688618814, 6235376638608, 1810793539845714, 636329871517885332, 282006422882452989030, 145933818284739352119000, 91644646853849910546846330

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,2

LINKS

Table of n, a(n) for n=0..13.

FORMULA

a(n) ~ 2 * (2*n-1)! * (4*n)^(log(1+sqrt(2))/2) / GAMMA(log(1+sqrt(2))/2). - Vaclav Kotesovec, Oct 24 2013

MATHEMATICA

Table[n!*SeriesCoefficient[Exp[ArcTanh[x]*ArcSinh[x]], {x, 0, n}], {n, 0, 40, 2}] (* Vaclav Kotesovec, Oct 24 2013 *)

CROSSREFS

Sequence in context: A009613 A012388 A297368 * A188904 A189104 A347914

Adjacent sequences: A012749 A012750 A012751 * A012753 A012754 A012755

KEYWORD

nonn

AUTHOR

Patrick Demichel (patrick.demichel(AT)hp.com)

STATUS

approved